ACMNA055 MA2-5NA This is a subtraction game, for 2 - 4 students, using two-digit numbers to 50. It is played as a rummy game i.e. players collect a card, attempt to match it with subtraction sums on the cards in their hand and then discard a card. A checking card, to be used by another player or helper, is included on the back of the instruction card. 1 game = 84 cards, instructions and a checking card.